We are currently working on a MAUI project, versioned on git. I got View containing a picker, but in my case the picker isn't visible. I can click and interact with it, and the logic is still here. Furthermore, my colleagues have the right display (see below).
my colleagues' popup:

mine:
I haven't any more details to provide, because I don't even know were to find them. This thread seems to be a similar case. Maybe it could help.
I've already uninstalled and reinstall VS22, all nuggets, et delete and cloned the git repo.
This is likely a bug from MAUI, as a workaround you can apply the below style in your "Platforms/Windows/App.xaml":
Win UI reference
Related MAUI issue on Github